From c5f9fab13a960e0f920f177133b593c494f1f68c Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sat, 6 Jun 2026 03:16:19 +0000
Subject: [PATCH 1/2] test: add tests for getMostActiveHour edge cases

Co-authored-by: is0692vs <135803462+is0692vs@users.noreply.github.com>
---
 src/lib/__tests__/yearInReviewUtils.test.ts | 43 +++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/src/lib/__tests__/yearInReviewUtils.test.ts b/src/lib/__tests__/yearInReviewUtils.test.ts
index c964d7bc..8f0256bc 100644
--- a/src/lib/__tests__/yearInReviewUtils.test.ts
+++ b/src/lib/__tests__/yearInReviewUtils.test.ts
@@ -78,6 +78,31 @@ describe("buildHourlyHeatmapFromCommitDates", () => {
 
 
 describe("getMostActiveHour", () => {
+    it("returns 0 if heatmap does not have 7 rows", () => {
+        const heatmap = Array.from({ length: 6 }, () => Array.from({ length: 24 }, () => 0));
+        expect(getMostActiveHour(heatmap)).toBe(0);
+    });
+
+    it("returns 0 if a row does not have 24 hours", () => {
+        const heatmap = Array.from({ length: 7 }, () => Array.from({ length: 24 }, () => 0));
+        heatmap[0] = Array.from({ length: 23 }, () => 0);
+        expect(getMostActiveHour(heatmap)).toBe(0);
+    });
+
+    it("returns 0 if a row is not an array", () => {
+        // @ts-expect-error Intentionally invalid input
+        const heatmap: number[][] = Array.from({ length: 7 }, () => Array.from({ length: 24 }, () => 0));
+        // @ts-expect-error Intentionally invalid input
+        heatmap[0] = "not-an-array";
+        expect(getMostActiveHour(heatmap)).toBe(0);
+    });
+
+    it("returns 0 if an element in a row is not finite", () => {
+        const heatmap = Array.from({ length: 7 }, () => Array.from({ length: 24 }, () => 0));
+        heatmap[0][0] = NaN;
+        expect(getMostActiveHour(heatmap)).toBe(0);
+    });
+
     it("returns 0 if heatmap is malformed (not 7x24 matrix)", () => {
         expect(getMostActiveHour([])).toBe(0);
         expect(getMostActiveHour([[1,2,3]])).toBe(0);
@@ -176,6 +201,18 @@ describe("getMostActiveDayFromCalendar", () => {
 });
 
 describe("buildHourlyHeatmapFromCommitDates - edge cases", () => {
+    it("falls back to full date parsing when fast path check fails", () => {
+        const commitDates = ["2023-01-01T10:00:00+00:00"]; // Invalid timezone ending format for fast path, uses T but not Z
+        const heatmap = buildHourlyHeatmapFromCommitDates(commitDates);
+        expect(heatmap[0][10]).toBe(1);
+    });
+
+    it("falls back to full date parsing when new Date parsing fails", () => {
+        const commitDates = ["2023-13-45T10:00:00Z"]; // Invalid date part
+        const heatmap = buildHourlyHeatmapFromCommitDates(commitDates);
+        expect(heatmap.flat().reduce((sum, count) => sum + count, 0)).toBe(0);
+    });
+
     it("falls back to full string parsing for unparseable hour data", () => {
         const heatmap = buildHourlyHeatmapFromCommitDates(["2023-01-01TX0:00:00Z"]);
         const totalCommits = heatmap.flat().reduce((sum, count) => sum + count, 0);
@@ -210,4 +247,10 @@ describe("buildHourlyHeatmapFromCommitDates - edge cases", () => {
         const heatmap = buildHourlyHeatmapFromCommitDates(commitDates);
         expect(heatmap[0][10]).toBe(0);
     });
+
+    it("falls back to full date parsing when timezone check fails parsing", () => {
+        const commitDates = ["2023-01-01T10:00:00+XX:XX"];
+        const heatmap = buildHourlyHeatmapFromCommitDates(commitDates);
+        expect(heatmap.flat().reduce((sum, count) => sum + count, 0)).toBe(0);
+    });
 });

From 4620094ba534e0abdd359282683735f930c7f351 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sat, 6 Jun 2026 03:19:34 +0000
Subject: [PATCH 2/2] test: remove unused ts-expect-error directive

Co-authored-by: is0692vs <135803462+is0692vs@users.noreply.github.com>
---
 src/lib/__tests__/yearInReviewUtils.test.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/lib/__tests__/yearInReviewUtils.test.ts b/src/lib/__tests__/yearInReviewUtils.test.ts
index 8f0256bc..3f99bf4d 100644
--- a/src/lib/__tests__/yearInReviewUtils.test.ts
+++ b/src/lib/__tests__/yearInReviewUtils.test.ts
@@ -90,7 +90,6 @@ describe("getMostActiveHour", () => {
     });
 
     it("returns 0 if a row is not an array", () => {
-        // @ts-expect-error Intentionally invalid input
         const heatmap: number[][] = Array.from({ length: 7 }, () => Array.from({ length: 24 }, () => 0));
         // @ts-expect-error Intentionally invalid input
         heatmap[0] = "not-an-array";